Construction and characterization of molecular organizations are summarized. Copolymer consisting of anionic block and perfluorinated block forms micelle, and its size is decreased in addition of HCl or NaCl, different from the case of low-molecular-weight ionic amphiphiles. Amphiphiles with chirality or functional groups for the intermolecular interaction form fibers, but the structures differ from each other. In some cases, such fibers present liquid crystal phase. Photocyclodimerization proceeding in the molecular assemblies is most reactive in vesicle. The stereochemical selectivity of the product depends on not only the assembly structure but also the binding of reaction molecules on assemblies. Metal nanoparticles constructed under the presence of protection agent display two-dimensional array on the substrate with interdigitated monolayer or bilayer arrangement of alkyl chains protecting nanoparticles. Water-soluble nanoparticles are prepared in the presence of dendrimers as protection agent. Hydrocarbon amphiphiles with analogous chemical structures are mixed in two-dimensional Langmuir-Blodgett films but dye surfactant is phase-separated from the micro domain of arachidic acid. While the mixtures of hydrocarbon and fluorocarbon amphiphiles always form the separated domains, the mixing of two fluorocarbon amphiphiles depends on the fluorocarbon chain length. Various types of intersurface interactions are observed on the surfaces adsorbed amphiphiles and dendrimer. Those are electrostatic repulsion, hydrophobic interaction, adhesion, solvation, and steric repulsion forces.

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The term “fluorescent lipid peroxidation products (FLOP)” refers to the fluorescent chromophoric structure of age pigments “lipofuscin” or “ceroid” that accumulate in cells as the autofluorescent lysosomal storage bodies during senescence. The chemical structure and mechanisms of formation of age pigments are not known in great detail. In attempts to elucidate the mechanisms of age pigment formation, studies have been conducted to evaluate the effects of a variety of experimental manipulations on the in vivo as well as in vitro formation of FLOP. The formation and lysosomal storage of FLOP and the lipid nutrition for human health studied in our laboratory are reviewed.

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A series of bile acids/salts acting as surfactants in vertebrate living bodies have been studied in regard to their colloid-and-interfacial properties of their aqueous systems such as surface activity, micelle, polymer-like aggregate or gel formation, solubilization or emulsification, adsorption at air/water and/or at water/solid interfaces etc, which are exhibited by the respective single species and their mixed systems. Of these properties, the aggregation behavior of the respective species which depends on species itself and given conditions such as pH, added salt concentration and temperature is overviewed in this article primarily according to the past work done by the present author and his coworkers.

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This review describes the preparation and properties of new types of sugar-derived amphiphilic compounds and their application to enantioselective hydrolysis of an amino acid ester, selective transport of sugars, and metal cation recognition. Two types of new sugar-derived surfactants were prepared from glucono-1, 5-lactone and N-acetyl-D-glucosamine, respectively, as a starting material, via several reaction steps which include transacetalization of two hydroxyl groups of the sugars with long-chain alkyl aldehyde or ketone dimethyl acetal. Among them, the nonionic surfactants derived from glucono-1, 5-lactone and the anionic surfactants derived from N-acetyl-D-glucosamine showed excellent ability to lower surface tension. The surfactants bearing sugar-amide head groups showed enantioselective micellar catalysis for the hydrolysis of p-nitrophenyl ester of phenylalanine hydrogen bromide. The hydrolysis rate and the enantioselectivity were influenced by the structure of the sugar moiety and the alkyl chain length of the surfactant. The reversed micelle formed by gluconamide-type amphiphilic compounds functioned as an efficient carrier for selective transport of sugars through a bulk liquid membrane. The selectivity for transport of sugars in this system was closely related to the hydrophobicity of the sugar molecule. Amphiphilic cycloinulohexaoses were found to complex with K⁺, Rb⁺, and Ba²⁺ in water, but negligibly with Li⁺ and Na⁺, on the basis of the changes in their cmcs in the presence and absence of the corresponding metal chlorides.

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